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Electron Confinement Induced by Diluted Hydrogen-like Ad-atoms in Graphene Ribbons

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 نشر من قبل Jhon W. Gonz\\'alez
 تاريخ النشر 2015
  مجال البحث فيزياء
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We report the electronic properties of two-dimensional systems made of graphene nanoribbons which are patterned with ad-atoms in two separated regions. Due to the extra electronic confinement induced by the presence of the impurities, we find resonant levels, quasi-bound and impurity-induced localized states, which determine the transport properties of the system. Regardless of the ad-atom distribution in the system, we apply band-folding procedures to simple models and predict the energies and the spatial distribution of those impurity-induced states. We take into account two different scenarios: gapped graphene and the presence of randomly distributed ad-atoms in a low dilution regime. In both cases the defect-induced resonances are still detected. Our findings would encourage experimentalist to synthesize these systems and characterize their quasi-localized states employing, for instance, scanning tunneling spectroscopy (STS). Additionally, the resonant transport features could be used in electronic applications and molecular sensor devices.



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